Blood clots (e.g., emboli and thrombi) are examples of blockages that may form in mammalian blood vessels. A clot in an individual's blood vessel may become dangerous when it restricts blood flow, thereby placing the individual at risk for medical traumas, such as a stroke or a heart attack. Therefore, there may be a need to remove clots that are lodged within blood vessels.
A variety of devices and procedures have been used to remove clots from blood vessels. For example, a catheter with a balloon on its distal tip may be inserted into a blood vessel and passed through the clot, after which the balloon is inflated. The balloon may then be withdrawn from the blood vessel to remove the clot.
Another example of a clot removal device is a catheter containing a spiral section at its distal end. The catheter with spiral section may be delivered to a clot site within a blood vessel, and the spiral section may then be used to cut into the clot. The spiral section, therefore, may grasp to an inner portion of the clot prior to withdrawing the clot from the blood vessel.
One risk that exists with clot removal devices is that a piece of the clot may break away during the removal process, travel through the vasculature, and cause traumatic damage. This may occur for various reasons. For example, if the clot removal device passes through the clot prior to deployment, the pre-deployment activity can disrupt the clot, causing pieces to break away. Further, there is an increased risk of deploying a device in uninvolved distal territory. There is a need for devices and methods that may allow a clot to be removed from a blood vessel, while reducing the risk that a clot or portion of a clot may become dislodged during the removal process, causing further risk to the patient.